MODEL AV-680

INSTRUCTION MANUAL

308 Industrial Park Road

Starkville, MS 39759 USA

Ph:(662) 323-9538 Fax: (662) 323-6551

Made in USA 925-0680-REV A2

Introduction

Hy-Gain is proud to deliver the AV-680 Nine Band Vertical. Drawing on our many years of Amateur Radio HF and VHF antenna design experience, we have produced a wellengineered antenna capable of maximum efficiency, unmatched performance, and superior construction.

Computer optimization of the AV-680 design yields the most efficient 3/8 wavelength electrical design with maximum gain and low angle of radiation for long distance communication. No traps are used to achieve nine band performance. The AV-680 is resonant on 6, 10, 12, 15 and 17 meters with individual 3/8 wavelength radiators. The center radiator resonates on 20, 30, 40 and 80 meters using parallel end loaded Teflon wire coils. Capacity hats on these bands give wide 2:1 VSWR bandwidth and the antenna is kept to a height of 27 feet by the low inductance coils. There are no "tricks" or

"mystery resonances" used for impedance matching on any band.

No long-wire radials or counterpoise kits are necessary for operation of the AV680.

The AV-680 is self contained for simple, convenient portable or fixed operation.

Mechanical construction of the AV-680 is designed for extreme light weight and high wind survival. Aircraft grade 6063-T832 aluminum and high strength fiberglass are used for the entire radiator. The trap-free design presents a very low wind surface area. Bulky tubing is not required to support unwieldy traps. The broad 2:1 VSWR bandwidth on all bands lessens large frequency shifts seen in other antennas when the antenna is wet or iced.

The AV-680 is covered by our Hy-Gain Warranty and supported by our customer service team. We would like to thank you for purchasing this product from us and ask that you let us know of any suggestion you may have. With proper assembly, installation, and maintenance, your AV-680 will provide years of faithful service.

Theory of Operation

The AV-680 HF Multiband Vertical antenna consists of an end fed radiator that is resonant in the 6, 10, 12, 15, 17, 20, 30, 40 and 80 meter amateur frequency bands. Resonances on each band are the result of impedance matching a 3/8 wavelength element with a broadband RF transformer. The characteristic impedance at the base of the 3/8 wavelength radiator is in the order of a few hundred ohms.

To match this impedance two tools are employed. First a counterpoise of 72" spokes is mounted at the AV-680 base. The capacitance from this ground plane

2

helps lower the base impedance. Second, a 4:1 toroidal transformer (voltage balun) steps the base impedance down to 50 ohms. This transformer uses a ferrite core for high power capability. Also, the windings are made of twisted pair wire to improve coupling and reduce loss. A second high power transformer is configured as a 1:1 current balun to help stop RF from traveling back on the feedline shield. The radiator of the AV-680 is at DC ground potential for static drain. This is accomplished by a radio frequency choke in the matching circuit.

The center radiator of the AV-680 supports 1/4 wavelength stubs for 6 , 10, 12 and 17 meters. The stubs are placed approximately one tenth of a wavelength (electrically 1/8 wavelength) above the AV-680 base. At the top of each stub the impedance is very high at the frequency the stub is tuned. This high impedance stops, (chokes) RF at this point creating a resonant 3/8 wavelength radiator. There is minimal loss using this method as compared to standard trap circuits. Also, VSWR bandwidth is not restricted by the °Q" of trap components. For 20, 30, 40 and 80 meters, a coil and capacity hat are used on each band to create a 3/8 wavelength radiator. The coils are mounted at the top of the center radiator. These foer coils are connected in parallel. Parallel connection separates each band to allow individual band tuning and has less loss than does series connection.

Also, the AV-680 coils have significantly less loss than a standard trap because the AV-

680 capacity hats exhibit greater capacitance than a typical trap, therefore, less inductance is required.

Antenna Location

The best performance for receiving and transmitting will be obtained by mounting the antenna in a clear location above or away from buildings, buildings, towers, feedlines, utility wires, and other antennas. While your own ingenuity and particular circumstances will determine the final mounting method, remember, any object within 75 feet from the base of the antenna can influence the performance of the AV-680.

WARNING: Always mount this antenna so that it is out of the reach of adults as well as children and pets. The counterpoise rods can cause injury and or severe RF burns.

·

NEVER mount this antenna in a location that will permit unsuspecting people to come in contact with any part of the antenna.

·

NEVER mount this antenna where a mechanical failure might allow the antenna, antenna support or feedline to contact power lines or other utility wires.

·

ALWAYS ground the feedline at the point where it enters a building to a good earth ground for lightning protection.

·

ALWAYS follow the guidelines for antenna installations as recommended by the US Consumer Product Safety Commission.

3

Antenna Mast

The recommended support mast for the AV-680 is steel water pipe between the sizes of

1-3/4" OD to 2 1/2" OD and with a length that will place the antenna base at a safe height.

Do not use thin walled conduit, aluminum tubing, or "TV" mast. The AV-680 is designed to operate at a height of 8 or more feet for proper performance. Placement on the side of a house or garage at eaves level is acceptable as long as the counterpoise whips will not be in contact any snow on the roof. Placement above metal roofs is acceptable if the antenna base is at least 5 feet or more above the metal surface.

Antenna Grounding

Although the AV-680 is designed to operate efficiently without the requirement of an earth ground, SAFETY GROUNDING must still be provided to protect equipment, property and persons from the hazards of lightning strikes and other weather related electrical discharges. In addition the coaxial cable feeding the antenna should have the shield grounded to eliminate the risk of any indoor equipment failure from allowing hazardous voltages from appearing indoors and creating a shock hazard. The support mast should be grounded with a large diameter ground wire.

The AV-680 is DC grounded for static discharge. This is accomplished with a choke coil in the Matching Unit. This coil could fail under high voltage spikes from a near or direct lightning strike.

Additional protection can be accomplished by grounding the shield of the coax where it enters the building to a good earth ground or directly burying the cable in the earth for several feet before it enters the building. The coaxial cable should be totally disconnected from the station during threatening weather conditions for maximum lightning protection.

Antenna Guying

For normal operation up to 65 mph winds, the AV-680 will not require guying. For extreme locations such as tall building rooftops, a safety guy is recommended. Use

Dacron® rope to guy the center radiator. Attach ropes 14 feet above the antenna base. Use care not to disturb the radiator stubs.

Customer Supplied Components

• Quality low-loss 50 ohm coax cable with PL-259 connectors

• VSWR Analyzer (MFJ-259B or equiv.) or HF transceiver with VSWR meter

.

Mounting mast with required hardware to provide sturdy support

4

Tools Required For Assembly

• 1/4" Standard Blade Screwdriver

• #1 Phillips Screwdriver

#2 Phillips Screwdriver

3/8" Open End Wrench

3/8" Nut Driver

5/16" Nut Driver

5/16" Open End Wrench

• 7/16" Nut Driver

• 7/16" Open End Wrench

• 10 nun Open End Wrench

• Tape Measure 20'

• Safety Glasses

• Pliers

Safety Precautions

WARNING: You can be killed if the antennas, feedline, or the equipment used to install the antenna accidentally contacts any utility lines. Never install an antenna near power lines!

·

Be careful while climbing and carrying the antenna. It is heavy enough to cause you to lose your balance if it is handled too casually or if any part of the antenna snags on a gutter, ladder, tree, or other item.

·

Mount the antenna high enough and in the clear so that it is out of reach by any person or pet. Do not allow trees or other structures near the radiator portion of the antenna. The counterpoise whips can cause serious eye injury.

·

Ensure that the mast is sturdy enough to support the weight of this antenna including the windload of the antenna.

5

Parts List

Part Number Part Description

17-AV680-4 Instruction Manual Bag

17-AV640-1 Parts Bag #1

17-AV640-2 Parts Bag #2

17-AV640-3 Parts Bag #3

80-AV680-1 AV680 Matching Unit

810-0620-1

11-0680-1

Base Insulator 1-1/4" x 12"

AV-680 Coil Assembly

810-0640-5

810-0640-2

810-0640-3

810-0640-4

Base Tube 1-1/2" x 12"

Radiator Section 1-1/2" x 72"

Radiator Section 1-3/8" x 75"

Radiator Section 1-1/4" x 75"

810-0640-9 Radiator Section 5/8" x 36"

17-AV680-9 Small Tube Bundle

17-AV680-10 Spoke Bundle

735-0680

810-AV640-23

Antenna Mounting Plate

Radiator Section 3/4 x 22”

ID Number Quantity

IM

PB1

PB2

1

1

1

PB3

MU

IN

L1

BA

BB

BC

BD

BF

ST

BS

1

1

1

1

I

1

1

1

1

1

1

MB 1

BE 1

Small Tube Bundle 17-AV680-9

Part Number Part Description

810-0680-55P Stub Section 3/8" x 55"

810-0680-60 Stub Section 3/8" x 60"

810-0680-44 Stub Section 3/8" x 44"

810-0680-6 Stub Section 5/16" x 6" Rod

758-2764 72" Stainless Steel Whip

ID Number Quantity

E1

E2

E3

CP

4

2

2

8

CW 7

Spoke Bundle 17-AV680-10

810-0680-48 1/8" 48" Aluminum Rod

810-0680-36 1/8" 36" Aluminum Rod

810-0680-25 1/8" 25" Aluminum Rod

810-0680-15 1/8" 15" Aluminum Rod

810-0640-28 1/8" 40" Aluminum Rod

SP1

SP2

SP3

SP4

Spares

8

4

4

4

2

6

17-AV680-4

Part Number Part Description

925-AV680 AV-680 Instruction Manual

925-0006 Hy-Gain Warrant Card

784-1780 Warning Label

ID Number Quantity

MN

WC

WL

1

1

7

17-AV680-1

Parts Bag #1 Part Description

656-0375S

656-0500S

656-1250S

6-32 x 3/8" Screw SS

6-32 x 1/2" Screw SS

6-32 x 1-1/4" Screw SS

656-1500S

656-1750S

6-32 x 1-1/2" Screw SS

6-32 x 1-3/4" Screw SS

705-0632S-K 6-32 Nut W/Lock SS

660-0375S 10-32 x 3/8" Screw SS

711-1037S #10 Lock Washer SS

745-3104S #4 Hose Clamp SS

705-1032S-NL 10-32 Nut Nylon Insert SS

662-2000S 1/4-20 x 2" Bolt SS

705-2520S-NL 1/4-20 Nut Nylon Insert SS

745-3110S

745-3112S

765-1002

1" Hose Clam SS

1 1/2" Hose Clam SS

1/8” Rod Cap

745-3108

745-3116S

765-1062

Counterpoise Ring SS W/tabs

#16 Hose Clamp SS

Plastic Ca 5/8"

ID Number Quantity

S1

S2

S4

S3

S5

N1

S6

W1

N3

S8

48

12

12

6

2

82

12

8

12

8

4

N5

HC2

HC1

RI

C2

2

3

1

8

1

3

17-AV680-2

Parts Bag #2

735-1610

195902

170035

561016

555694

013209

543792

564792

555747

Part Description

Radiator Clamp Bracket

Mast Saddle

AL mast block

3/8 split washer

3/8 x 16 nut

3/8 u-bolt

5/16 u-bolt

5/16 split washer

5/16 x 18 nut

17-AV680-3

Part Bag #3 Part Description

ID Number Quantity

RB

SB2

SB1

16

2

SW1

NB1

UB1

4

2

2

4

UB2

SW2

NB2

2

4

4

ID Number Quantity

735-1618 Single Stub Base Bracket

735-1611 Dual Stub Base Bracket

738-0680-3 Single Stub Insulator

738-0680-1 90 Degree Stub Insulator

738-0680-2 180 Degree Stub Insulator

11-AV620-1 Jumper Wire

SB1

SB2

P3

P1

P2

J1

2

2

2

1

5

1

Plastic parts

90 Degree Stub Insulator

P/N 738-0680-1 Qty (2)

ID # P1

180 Degree Stub Insulator

P/N 738-0680-2 Qty (2)

ID # P2

Single Stub Insulator

P/N 738-0680-3 Qty (5)

ID # P3

Aluminum parts

Single Stub Base Bracket

P/N 735-1618 Qty (2)

ID # Sb1

Radiator Clamp Bracket

P/N 735-1610 Qty (16)

ID # RB

Dual Stub Base Bracket

P/N 735-1611 Qty (1)

ID # Sb2

8

TASK I

Center Radiator Assembly

( ) Refer to Figure A to assemble the Center Radiator. Attach BA tubing section to either end of the Base Insulator (IN) with (2) 1/4-20 x 2" bolts (S8) and (2) 1/4-20 nylock nuts

(N5). Do not tighten the nuts at this time.

( ) Find the (2) counterpoise rings (RI) The ones with the tabs. . Press the flat sides of the rings together and slide them onto the Base Insulator (IN). Leave rings loose at this time.

( ) Attach the drilled end of tubing section BB to the Base Insulator (IN) with (2) 1/4-20 x 2" bolts (S8) and (2) 1/4-20 nylock nuts (NS). Do not tighten the nuts at this time.

( ) Place (1) hose clamp (HC 1) over the slotted end of tubing section BB. Slide unslotted end of BC tubing section into BB until it stops. Tighten hose clamp. NOTE: For protection against oxidation, a conductive paste such as NoAlox® may be used between telescoping pieces of aluminum tubing only.

Do not apply the paste to insulators or coax connections.

( ) Place (1) hose clamp (HC 1) over the slotted end of tubing section BC. Slide unslotted end of BD tubing section into BC. Tighten hose clamp.

( ) Place (1) hose clamp (HC 1) over the slotted end of tubing section BD. Insert AV-680

Coil Assembly (LI) 4 inches into tubing section BD. Tighten hose clamp.

( ) Install two sections BE and BF on top of the coil assembly. Use the 6-32 x 1- ¼ screw and nut to secure BE into the top of the coil assembly. Slide BF into BE three inches and place the HC2 hose clamp over the slotted end and tighten. Install the jumper on the top of the loading coil to the tube BE using a 6-32 x 1-1/4” screw and nut.

( ) Place 5/8" plastic cap (C2) on end of tubing section BF

TASK II

Stub Base Bracket Assembly

( ) Refer to Figure B for Stub Base Bracket Assembly. Study Figures B and C to learn how the stub base brackets are attached for each band. Note how the brackets are offset

90 degrees from each other for proper antenna assembly.

( ) Find the aluminum Stub Brackets (SB 1 & SB2). Attach a Radiator Bracket (RB) to each Stub Bracket with (2) 6-32 x 3/8" screws (S I) and (2) 6-32 lock nuts (N1) as shown in Figure B.

( ) Find a Single Stub insulator (P3). Attach it to a Radiator Bracket (RB) with (2) 6-32 x

3/8" screws (S I) and (2) 6-32 lock nuts (NI).

9

( ) Mount each Stub Base Bracket to the AV-680 Radiator using a Radiator Bracket

(RB), (2) 6-32 x 1 1/2" screws (S3), and (2) 6-32 lock nuts (N1). Place the Single Stub insulator opposite the Single Stub Base Bracket shown in Figure C.

( ) NOTE the degrees offset for each bracket and the distance from the base insulator

(IN) in Figure C. Position the Stub Brackets ABOVE the Radiator Brackets.

TASK III

Stub Insulator Assembly

( ) Place the AV-680 Radiator on a flat surface such as a driveway or garage floor. This will aid in mounting the Stub Insulators by keeping them aligned with each other.

( ) Refer to Figure D for Stub Insulator Assembly. There are three types of stub insulators: Single, 90 Degree and 180 Degree. The 180 Degree insulators are used with a

Single Stub insulator to make a Three Stub insulator. The locations of the Single insulators are labeled «A", 90 Degree insulators are labeled "B" and the Three Stub insulators are labeled "C".

( ) Attach 90 Degree Stub Insulators (P1) to a Radiator Bracket (RB) using (2) 6-32 x

3/8" screws (S1) and (2) 6-32 Keps nuts (N1) as shown in Figure D.

( ) Attach Single Stub Insulators (P3) to a Radiator Bracket (RB) using (2) 6-32 x 3/8" screws (S l) and (2) 6-32 Keps nuts (NI).

( ) For Three Stub Insulators, attach a Single Stub and a 180 Degree Stub Insulator (P3

& P2) to a Radiator Bracket (RB) using (2) 6-32 x 1/2" screws (S2) and (2) 6-32 Keps nuts (N1).

( ) Mount the Stub Insulators on the AV-680 Radiator using a Radiator Bracket (RB), (2)

6-32 x 1 1/4" (S4) screws, and (2) 6-32 Keps nuts (N1). USE the dimensions in Figure E to space and rotate the insulators into their proper locations. Position the Stub Insulators

ABOVE the Radiator Brackets.

TASK IV

Stub Assembly

( ) Refer to Figure F for the stub assembly diagram.

Assemble the stubs on the antenna.

( ) All four stubs share the same base tube ( E1 ) which has the threaded insert in one end. This end attaches to one of the metal brackets at the bottom of the antenna. You may attach all four of these elements sections to the antenna using the 10-32 screw and lock washer. Use “Figure G” For location of each Stub.

10

( ) SIX METER STUB: The six meter stub consist of only the first section (E1) and the coupler (CP) and is attached to the lowest metal clamp on the antenna “Figure C”

Slide the coupler into the top of the stub and use a hose clamp to secure it. This rod will be used to adjust the length of the stub.

TEN AND TWELVE METER STUB:

( ) TEN AND TWELVE METER STUB. These two stubs are attached to the 180 degree metal bracket above the 6 meter stub “Figure C”. It does not matter which side you chose for each band. They will work the same in either place. Assemble them on the antenna by sliding the sections down the insulators and connecting them using the couplers (CP) and the small hose clamps. The 10 meter uses the E1, and E3 sections which makes it slightly shorter than the 12 meter section which uses E1 and E2. Insert a coupler into the top of each section and secure it with a hose clamp.

( ) SEVENTEEN METER STUB: This is the longest stub and consist of all three sections E1,E2 and E3. This element attaches to the uppermost metal bracket and extends all the way up to the loading section of the antenna. Insert each section into the insulators and connect them using the couplers (CP) and hose clamps. Insert one coupler into the top section and secure with the hose clamp.

11

TASK VI

Matching Unit Mounting

( ) Refer to Figure H for the mounting location of the Matching Unit (MU). Use the pair of bolts through the Base Insulator (IN) to mount the MU as shown in Figure H.

Remove the (2) 1/4-20 nuts (N5) from the (2) 1/4-20 x 2" bolts (S8) previously installed.

( ) Place the Matching Unit on the bolts and secure in place with the (2) nuts. Be sure the coax connector end of the Matching Unit faces the base (bottom) of the antenna.

( ) Using a 6-32 Keps nut (N1), connect one end of the jumper wire (JI) to the counterpoise terminal of the Matching Unit. Do not over-tighten this nut. The other end of the jumper wire is attached later.

TASK VII

Counterpoise Assembly

( ) Refer to Figure H to assemble the counterpoise.

( ) Loosely attach the counterpoise rings (RI) to the base insulator (IN) with (2) 6-32 x 1

3/4" screws (S5) and (2) 6-32 Keps nuts (NI).

( ) Loosely attach the counterpoise rings (RI) together with (8) 10-32 x 3/8" screws (S6) and 10-32 nylock nuts (N3).

( ) Place the (7) 72 inch (183 cm) counterpoise whips (CW) into the slots provided in the sides of the rings. The slot facing the Matching Unit (MU) does not receive a whip.

( ) Tighten the 10-32 nuts (N3) around the rings to secure the whips.

( ) Place the loose end of jumper wire (Jl) under the closest 6-32 screw (S5) that holds a ring to the base insulator as shown in Figure H. Tighten the (2) 6-32 nuts (N l) that secure the rings to the base insulator.

( ) Attach a warning label to the end of each whip as shown in Figure H.

TASK VIII

Antenna Mounting Plate Assembly

( ) Refer to Figure I for assembly of the Antenna Mounting Plate (AM).

( ) Attach the antenna to the mounting plate first as the u-bolt nuts will not be accessible onec the mast is attached. Place a drop of oil on the threads of each u-bolt to prevent stainless components from seizing together.

12

( ) The smaller u-bolt should be on top and center between the two ¼-20 bolts in the mast. If the lower bolt contacts the bracket then rotate it around the mast until it clears.

( ) Tighten the (4) bolts that hold the antenna to the bracket.

( ) Place the (2) Larger U-bolt assemblies into the holes in the antenna mounting plate as shown in Figure I. Leave nuts loose until installation of the antenna.

TASK IX

Capacity Hat Assembly

( ) Refer to Figure J for assembly of the five Capacity Hats.

( ) Rotate the AV680 Coil Assembly (Ll) so the top end of the 17 meter stub is away from the AV680 Coil Strap as shown in Figure J. To rotate the coil assembly, loosen the lower coil hose clamp (HC 1). Tighten hose clamp when finished.

( ) Place (8) 6-32 x 3/8" screws (S1) and (8) 6-32 lock nuts (Ni) in each Counterpoise

Ring assembly on the AV-680 Coil Assembly (LI). Leave the nuts loose so that the spokes can be slid between the rings.

( ) There are spokes of lengths 15", 25",36" and 48". Place the spokes in the ring assemblies as shown in Figure J. The shorter spokes will be on the bottom end of the coil and the longer spokes will be on the upper end of the coil. The 40" spokes are spares. Tighten all hardware on the ring assemblies. Slide the 1/8 inch rod caps onto each of the rods. Use caution when around the spokes, they will poke you easily.

( ) NOTE: For tuning 20, 30, 40, and 80 meters, the lengths of the spokes are adjusted as shown in Figure J. It is suggested that the spokes be installed at their initial lengths. If any of the bands are resonant too low in frequency, one of the corresponding spokes can be pruned.

Only one spoke will r equire pruning but you may also pr une the one on the opposite side to m aintain a balanced look to the spokes.

Please refer to the Tuning section in figure J for more information.

Installation

The AV-680 antenna should be mounted at least 8 feet above ground. The main reason for this minimum height is safety. The AV-680 will work well at a minimum height of five feet but precautions from dangerous voltages must be taken.

Always have help for the installation process. Do not attempt to install the antenna alone. Review the requirements for Antenna Location and safety precautions regarding

Power Lines earlier in this manual.

13

The AV-680 may be roof mounted on a tripod or similar support. Keep the AV-680 base a minimum of 5 feet above the roof surface. This minimum dimension is the same for any roof material type. Attach a suitable ground wire to the support mast as mentioned in the Grounding section of this manual.

Tuning

The AV-680 should be checked with an VSWR meter before permanent installation to verify proper assembly and Matching Unit performance. Place the AV-680 at least 8 feet above ground and in as clear an area as possible. Connect the coax to the antenna base and test the VSWR using either an MFJ-259B VSWR Analyzer or equivalent or a transceiver and VSWR meter.

The 2:1 VSWR Bandwidth should be referenced to determine performance. VSWR measurements made at the antenna base are the most accurate and may show a slightly narrower VSWR bandwidth than the specifications chart lists. Be sure to use very low power (less than 5 watts) when measuring VSWR at the antenna base.

The AV-680 has few variables in its design. Therefore, VSWR should be very close to specifications. Each band can be adjusted individually. The element and stub lengths given in the drawings for the assembly of the antenna should tune the antenna close to the bottom of each band. Adjusting the stub lengths and trimming the capacity hats for each band will be needed to set the antenna your preferred section of the band.

Tuning 20, 30 and 40 meters

Individual adjustment of 20, 30, and 40 meters is accomplished by pruning one spoke in the corresponding capacity hat. Only one spoke needs to be adjusted and it does not matter which spoke is selected. Refer to Chart B to calculate the amount of spoke to prune and Figure J for spoke location. It is strongly suggested the AV-680 be assembled and tested with the spokes at the initial lengths to determine if any pruning is actually required. The initial length will tune the antenna to a frequency below each band.

Trimming the spokes will cause the resonant frequency to go up. Trim a small amount each time and recheck. If you go too far and the resonant frequency is too high, make a longer spoke from one of the 40" spare spokes and try again.

Tuning 80 meters

80 meters has an additional tapped loading coil that will allow for retuning the antenna after the spokes have been adjusted. For initial tuning, move the tap to the uppermost part of the coil so that all the turns are shorted out. Trim the spokes for the top of the band. Use the tapped loading coil to lower the operating frequency by moving the tap down. Set the antenna to the frequency you will be using the most. Use a Phillips screwdriver to secure the tap to the coil.

Tuning 6, 10, 12, 15 and 17 meters

Stub lengths can be adjusted for tuning the 6, 10, 12 & 17 meter bands. 15 meters usually will not require adjustment but can be adjusted by moving the loading coil on the main mast in and out of the main radiator. The total stub lengths are found in figure F.

These values will tune the antenna to the lower part of the band.

14

Please note the length of coax will vary the VSWR on certain bands. Lengths less than 50 feet have stronger harmonic resonances than longer lengths. If a particular band will not properly resonate, try adding 3-5 feet or more of coax. Record the resonant frequencies with and without the added coax. There will be a change in resonant frequencies on one or more bands. RF loss at HF is not a major problem with RG8X or larger coax. There will be a minimal performance difference between a 50 ft. length and a 75 ft. length of coax.

To lessen the possibility of RFI/TVI, roll up 6-8 turns of coax 8" inches diameter approximately one quarter wave (or multiple) from the base of the antenna. Use the quarter wave length of the frequency that causes the greatest amount of interference.

Maintenance

The AV-680 should be inspected mechanically at least once a year.

Normal wear and tear varies significantly with climate.

Anti-Oxidation paste such as NoAIOX® or others can be applied to the radiator tubing sections. Use small amounts. Do not place the paste on the coax connector or inside of the

Matching Unit.

Inspect the inside of the Matching Unit on a regular basis. Remove dirt, bugs, or questionable material. Look for any degradation of parts. High voltage static discharges (lightning) may cause a failure to the small coil in the Matching Unit. This coil is a protection device. Make sure it is in good shape.

Do not screw and unscrew the nylon insert nuts several times. If portable operation is desired, use stainless steel hardware without the nylon locking feature.

Tec hnica l A ssista nc e

Technical assistance is available during normal business hours on weekdays. Hy-Gain is located in the Central Time Zone. Our hours are 8:00 AM till 4:00 PM CST Monday through Friday.

Hy-Gain

308 Industrial Park Road

Starkville, MS 39759

Telephone (662) 323-9538

FAX (662) 323-6551 email " hy-gain@hy-gain. com "

Web Page " http://www.hygain.com

15

Service history has shown that most problems are operating or installation errors, rather than equipment failures. Most problems can be resolved over the telephone. Please contact our staff before shipping parts or equipment to us.

The packing material used to ship this antenna is designed to prevent shipping damage.

Please reuse the original shipping carton if possible. Hy-Gain will not be responsible for shipping damage on returned items with improper packing.

BAND

80 Meters

40 Meters

30 Meters

20 Meters

17 Meters

15 Meters

12 Meters

10 Meters

6 Meters

Trimming Affect

10 KHz per inch

17 KHz per inch

50 KHz per inch

100 KHz per inch

60 KHz per ½ inch

100 KHz per inch

150 KHz per ½ inch

100 KHz per ½ inch

300 KHz per ½ inch

CHART B

Spoke Tuning

16

BD

BC

C2

BF

INSERT 3 INCHES

BE

Connect jumper to tube

AV-680 L1

BB

S8,N5

4 places

BA

IN

Mount ring before tubing

17

FIGURE A

AV-680 Center Radiator Assembly

S3

SB2

RB

SB1

RB

S1

N1

A

6 Meter Stub

Base Bracket

Anten na Ba se

SB1

N1

BB

RB

N1

S1

B

10&12 Meter

Stub Base

Bracket

RB

N1

Anten na Ba se

SB2

S3

SB1

ALUMINUM

BLACK

PLASTIC

P3

RB

RB

S3

S1

N1

C

17 Meter Stub Base

Bracket and 6 Meter

Stub Insulator

Anten na Ba se

S1

SB1

N1

FIGURE B

Assembly of Stub Base Brackets

N1

18

SB1

P3

BB

RB

56”

47”

90 degree offset on this bracket

C

17 Meter Stub Base

Bracket and 6 Meter

Stub Insulator

B

10&12 Meter

Stub Base

Bracket

A

6 Meter Stub

Base Bracket

35”

BA

19

FIGURE C

Installation of Stub Base Brackets

N1

S1

D

90 Degree Stub

Insulator

N1

Anten na Ba se

S3

P2

RB

N1

E

S1

Three Stub

Insulator

P3

N1

Anten na Ba se

S3

S3

P3

RB

S1

F

Single Stub

Insulator

N1

FIGURE D

Installation of Stub Insulators

20

Anten na Ba se

P3

N1

BB

RB

21

23

24

N1 (2 places)

R1

(stainless ring with tabs)

S6 (8 places)

S5 (2 places)

WL 72” stainless whip (7 places) install whips after matching box

N3

One slot on the radial ring will be left empty.

This empty slot will make room for the matching box assembly.

Attach jumper from box to radial ring. Attach to ring with clamping screws.

FIGURE H

Conterpoise Assembly

25

Install the Antenna side first and tighten. You will not be able to access the nuts after the mast is installed.

NB2

UB1

Top u-bolt will sit between these two bolts. Rotate bracket until bottom bolt does not interfere with mount.

UB2

FIGURE I

Mounting Plate Assembly

SB2

SW1

SW2

NB2

NB1

SB1

26

Parts

NB2 4 X 555747 5/16 x 18 nut

SW2 4 X 564792 5/16 split washer

UB2 2 X 543792 5/6 U-bolt

SB2 2 X 195902 Steel saddle bracket

NB1 4 X 010209 3/8 x 16 nut

SW1 4 X 010208 3/8 split washer

UB1 2 X 013209 3/8 u-bolt

SB1 2 X 170035 AL saddle bar

MB 1 X 735-0680 Mast Bracket

80 meter spokes 48” x 8

Trim 80 meter spokes with tap at top of coil.

Set to 4 MHZ or your highest operating point on 80. Use the tap on the coil to tune the antenna to your frequency of choice.

40 meter spokes 36” x 4

30 meter spokes

20 meter spokes

25” x 4

15” x 4

Adjust 15 meters by sliding this section in and out of the main mast. Move it up to lower the operating frequency.

FIGURE J

Spoke Assembly

27

S6 (8 places including 2 already mounted)

Un-tighten the pre-installed screws and insert the rest of the screws and nuts loosely. Insert the spokes and tighten all eight screws.

R2

(Aluminum ring without tabs)

Pre-mounted

N1

80 Meter Capacity Hat Ring

1/8 AL spoke 48” (8 places)

S6 8 places. Loosely fit the screws and nuts into the ring. Insert the rods into the ring and tighten the screws.

The rings are shown further apart than they are on the loading section for illustration only. You do not need to unbolt them from the tube. Install the tube caps on the tips of the rods. The caps can be removed for tuning if needed.

N1

1/8 AL spoke

20,30,40 Meter Capacity Hat Rings

28 cap

Notes

29

30

31

LIMITED WARRANTY

hy-gain Warrants to the original owner of this product, if manufactured by hy-gain and purchased from an authorized dealer or directly from hy-gain to be free from defects in material and workmanship for a period of 12 months for rotator products and 24 months for antenna products from date of purchase provided the following terms of this warranty are satisfied.

The purchaser must retain the dated proof-of-purchase (bill of sale, canceled check, credit card or money order receipt, etc.) describing the product to establish the validity of the warranty claim and submit the original or machine reproduction of such proof-of-purchase to hy-gain at the time of warranty service. hy-gain shall have the discretion to deny warranty without dated proof-of-purchase. Any evidence of alteration, erasure, or forgery shall be cause to void any and all warranty terms immediately.

hy-gain agrees to repair or replace at hy-gain’s option without charge to the original owner any defective product under warranty, provided the product is returned postage prepaid to hygain.

Under no circumstances is hy-gain liable for consequential damages to person or property by the use of any hy-gain products.

Out-of-warranty Service: hy-gain will repair any out-of-warranty product provided the unit is shipped prepaid. All repaired units will be shipped COD to the owner. Repair charges will be added to the COD fee unless other arrangements are made.

This warranty is given in lieu of any other warranty expressed or implied.

hy-gain reserves the right to make changes or improvements in design or manufacture without incurring any obligation to install such changes upon any of the products previously manufactured.

All hy-gain products to be serviced in-warranty or out-of-warranty should be addressed to hygain, 308 Industrial Park Road, Starkville, Mississippi 39759, USA and must be accompanied by a letter describing the problem in detail along with a copy of your dated proof-of-purchase.

This warranty gives you specific rights, and you may also have other rights which vary from state to state.

308 Industrial Park Rd.

Starkville, MS 39759

925-0680-REV A